Locomotive type boiler



Sept 7, 1937. v. z. cARAcRlsTl LOCOMOTIVE TYPE BOILER File'd Aug. 22, 1955 5 Sheets-Sheet l INVENTOR l//RG//v/l/S Z C11/meeuw.

BY /M ATTORNEY Sept. 7, 1937.

V.I Z. CARACRISTI LOCOMOTIVE TYPE BOILER Filed Aug. 22, '1935 3 Sheets-Sheet 2 www .bukmll ATTORN EY Sept. 7, 1937. v v. z. cARAcRls-rl LocoMoTIv TYPE BOILER Filed Aug. 22, 1935 3 Sheets-Sheet 3 l n. 5 R M M f n R 7. N m 5 .R .N Um E .T V WA m 6 R Nw W u Y B Patented Sept. 7, 1937 UNiTl.

TATEii LOCOMOTVE TYPE BOILER Application August 22,

6 Claims.

The present invention relates to a boiler structure particularly adapted for use on steam locomotives and has as its objective to provide a boiler of high steam generating capacity which at the same time is of relatively light weight.

Liquid or pulverized fuel is best adapted to provide for the high rates of combustion required to attain high steam generating capacity and the boiler described herein is especially suited for ring with pulverized fuel. As is well known, any material increases in combustion rates are usually accompanied by losses due tounburned carbon. These losses arise from improper gas mixture in the combustion space, localized segregation of combustible gases away from contact with oxygen due to lack of turbulence of the mass of gases or frequency because of an unimpeded stream line flow of gases from the hre box over the arch and through the fire tubes, lack of proper regenerative heat action, or because of combinations of these factors.

In the present boiler structure a combination of waterv tubes about the fire box and combustion chamber and re tubes forwardly thereof provides ample heat absorbing surface together with gas areas suiiicient to maintain draft requirements and enables the provision of the large effective combustion space that is desirable when burning pulverized fuel. An effective mixture of air and fuel isl obtained by directing the fuel and secondary air entering the fire box in such manner as to cause turbulence of the gases and to avoid localized segregation of combustible gases or dead spots in the fire box.

The re box is provided with a specially constructed arch arranged to preclude the usual rush of gases in stream line flow over the rear end of the arch to the lire tubesby causing themk to flow through openings at the sides of the rear portion of the arch and laterally as well as forwardly thereof. This arrangement also retains the burning fuel Within the fire box for a period suicient to promote proper ignition and effective combustion. The walls of the re box are lined with circulating tubes which adjacent the side openings of the arch are provided with refractory tile so that a maximum regenerative effect is obtained as the gases ow from the fire box through passages which have refractory covered surfaces.

To be suitable for loco-motive use a boiler should posses the attribute which may be termed flexible self contained rigidity that is, it must be flexible enough to accommodate movements of the locomotive and provide for expansion or 1935, Serial No. 37,275

(Cl. l22--94) contraction of its heated surfaces while at the same time be sufficiently rigid to withstand the shocks and strains encountered in use. The present boiler is constructed and supported so that its parts while rigidly interconnected are flexibly carried on the locomotive frame.

rThe manner in which the above and other features and advantages are attained will best be understood upon consideration of the following detailed description of an illustrative embodiment of the invention as illustrated in the accompanying drawings in which:

Fig. l is a diagrammatic side elevational view of a locomotive boiler embodying the present invention;

Fig. 2 is a longitudinal sectional view through the fire box and combustion chamber of the locomotive;

Fig. 3 is an enlarged horizontal sectional view through the `fire box on the line 3 3 in Fig. 2 and shows the improved arch of the invention;

Fig. 4 is a View of the-rear head of the locomotive looking in the direction of the arrows in Fig. 2;

Fig. 5 is an enlarged sectional view through the rear head of the locomotive taken along the line 5-5 in Fig. 4;

Fig. 6 is a vertical sectional View through vthe re box along the line 6-6 in Fig. 2;

Fig. 7 is a vertical sectional view on the line` l-l in Fig. 2;

Fig. S is an enlarged fragmentary sectional view on the line -B in Fig. 6;

Fig. 9 is a fragmentary sectional View on the line 8 8 in Fig. 8 and illustrates the arch construction;

Fig. 10 is a view similar to Fig. 9 showing a modified arrangement of the arch construction;

Fig. 11 is an enlarged sectional view through the rear wall of the re box on the line ll--H' in Fig. 5; and

Fig. 12 is a vertical sectional View on the line l2-l2 in Fig. 2 and illustrates a sliding support for the boiler.

Referring to Vthe drawings, the numeral l0 designates a steam and water drum` disposed centrally above the lire box l2 and adjacent combustion chamber I3 of the locomotive. Drum l extends partly over a water barrel I4 and communicates with the upper central portion of the latter through several large nipples l5 (Figs. 2 and '7) suitably connected to the drum and barrel. The water barrel I4 is provided in usual manner with re tubes and flues connected between the front and back sheets i6 and Il. Other large nipples I8 connect the lower side portions of barrel M to a pair of water drums 2E disposed along and outwardly of the lower sides of combustion chamber i3 and fire box i2.

o The side walls of the fire box and combustion chamber are lined with closely spaced riser tubes 2i Connected at their lower ends into the drums 2Q and at their upper ends into individual headers 22 (Figs. 2 and 6) which in turn are conlO nected to the steam and water drum i@ by tubes 23 extending partially across the top of the re box and combustion chamber. The use of individual headers provides for unequal expansion or contraction of these tubes due to varying temperatures along the fire box and combustion chamb-er and also facilitates cleaning of these tubes.

A transversely extending header 2li connecting into drums 2) supplies water to arch tubes Sil extending rearwardly and upwardly in the re box into the forward side of a header 3| open centrally of its upper side, at 32, to the water space in drum lil and forming a downward extension of the latter. Header 24 also supplies water to slag screen tubes 25 disposed above the central portion of the bottom of the fire box and connected at their rear ends into a transverse header 2l into which closely spaced tubes 28 lining the back wall of the fire box are also connected. The upper ends of tubes 23 are staggered and alternate tubes connect into headers lil, di, (Figs. 2 and Ll) projecting from the sides of drum lil and communicating therewith.

A series of small pipes 42, having their upper sides within the drum cut away, conduct steam from the drum i3 to dry pipes i3 which supply the inlet headers M for superheater tubes t located in combustion chamber i3. Headers lll j are disposed vertically outside the wall tubes 2i and the heat absorbing portions of the tubes 4S project into the combustion chamber between more widely spaced side wall tubes 2| and extend transversely of the chamber, the tubes that connect with headers at opposite sides of the boiler being nested or intercalated longitudinally of the chamber i3, as shown in Fig. 3. The superheated steam headers il are also disposed vertically outside the wall tubes 2i and are connected to conduits i8 extending forwardly of the 5G sides of the locomotive to the throttle 58. The superheatcr is protected by a screen comprising staggered riser tubes 5l connecting' at their lower ends into a transverse header 52 communicating with drums E@ and connected radially into drum so i@ their upper ends. A dry pipe 53 receiving steam from drum le through pipes 5d, similar to pipes '32, supplies saturated steam to superheater elements 55 disposed within the lues of barrel id, the superheated steam from elements GO -iib mixing with that from elements i6 andpassing through throttle 5S and steam pipes 5t to the engines.

' The forward end of the steam and water drum it? is supported by the barrel i4 which is connested to transversely disposed flexible plates (Fig. 2) secured to the locomotive frame 6l. Further rearwardiy below the forward end of the fire box lil the drums are provided with supporting members E3 slidable upon the underlying portions of a transverse support 54 secured to the frame iii and providing for longitudinal movement of the boiler relatively to the frame. The members 53 interlock with the transverse supt as indicated in Fig. l2, to prevent lateral movement. Rearwardly of the back wall of re box l2 a transverse member 65 (Figs. 4 and 5) is connected to a flexible plate 66 secured to the locomotive frame. The outer ends of member 65 are formed to partially embrace and support the drums 29, also tying them together transversely of the frame. Mounted on and secured to member 55 is a built-up saddle-like support 6i having its upper and lower portions formed to partially embrace the steam drum l0 and water drums 2Q, respectively, so that the steam drum lil is rigidly supported at its rear end and tied to the water drums. The three drums, thus rigidly connected by the structure 65, 6l, are ilexibly connected and supported on the frame 6l by the member 66.

As may be seen in Figs. 3, 6, 8, and 9, the arch tubes 313 support refractory tile 33; the central portion 34 of the arch being completely covered from adjacent the forward end of fire box l2 to the back wall thereof, while the arch tubes along the sides of the rire box are only partially covered so that at the rear portion of the arch lateral openings 35 are provided through which the flames may pass. in the constructions selected for illustration herein the outermost row of refractory at each side covers the arch tubes from their forward ends to a point about midway of the fire box and in the adjacent row at each side the refractory extends further rearwardly but also terminates short of the back wall. Refractory tile 36 is also provided between these circulating tubes 2l located along the side walls from adjacent the rear wall of the fire box to a point somewhat beyond the forward ends of the lateral passages through the arch. Thus, at this portion of the re box its side walls are lined with alternate vertical rows of exposed tubes 2l and refractory tiling 36. Protective tiles 3l are provided on the backs of the remaining tubes 2l along the side walls to the forward end of combustion chamber i3.

In the arch arrangement illustrated in Fig. 10 the outer arch tubes Sila are partially depressed below the level of the adjacent inner tubes 301). Thus, the refractory tiles 34a supported between these tubes are downwardly inclined and form ledge-like side extensions of the central part of the arch. The gases escaping from beneath the arch through the side openings 35 near the rear thereof flow around the ends of the refractory tile 34a and over the upper surfaces 3de thereof as indicated by the arrows, with resulting regenerative eifect. Accordingly, this construction may be employed either in fire boxes having side wall tubes with 0r Without refractory tile or in those having a water leg side wall.

Secondary air for combustion is heated before being admitted to fire box i2 centrally of the rear end thereof and adjacent the bottom thereof. As shown in Figs. 6 and 8, the outer side casing 'm is spaced from the plating 'Fi covering the insulation 'i2 on the backs of the tiles 36, 3l associated with the side wall tubes 2|. Disposed between plating 'H and casing lil is a corrugated sheet 'i3 serving not only as a reinforcement for the casing sheet 'E0 but also to divide the air space into a series of vertically extending channels M. A similar corrugated sheet 'l5 lies in an air space formed above the tubes 23 connecting the headers 22 to drum Ill. Air enters through a longitudinally extending opening 'I6 (Fig. 6) along the top of the boiler at the sides of drum l@ and is caused to flow in parallel streams downwardly along the sides of the boiler through the passages 'M on both sides of sheet 13 to be dis- CII 8B inthe rear inner wall of the nre boX.

- openings 35.

charged into vthe fire box through openings 11 in its side wall' 'E8 near the bottom thereof.

Secondary air entering the combustion space is also heated as it passes to the central opening As is shown in Figs. 4 and 5, air is admitted through openings 8i in the rear supporting member for drum lll and passes between the outer casing plate 82 which is spaced from the insulation 83 lying outwardly of the refractory il@ associated with the rear wall tubes 28. yI-Iere also, parallel and vertical air passages 85 are formed by corrugations in a sheet 86. Air also enters through an opening 8l at the bottom of the rear wall of l the rire box and ilows upwardly toward the central opening 3G therein. The central portion of sheet 86 is dished to form a pocket 8B extending about the opening 3E! in the rear wall. The air passages formed by the corrugations near the middle of sheet 8S discharge air, flowing both downwardly and upwardly toward the wall opening 853, into the pocket t8. Air from the upper and lower vertical passages at the sides of pocket 88 is conducted thereto by transverse ducts 853 Iformed by depressing the sheet Bti laterally at the sides of the pocket. In ord-er to preserve the rigidity of sheet 86 the depressions made therein to form the ducts #i9 are preferably of less depth than the pocket 88.

Located in the central wall opening St are a pair of telescoped sleeves Si@ and 9i having flanges 92 by means of which they may be secured in place. The annular portions 93, 94 of the sleeves overlap are spaced so that air from the surrounding pocket t8 ows around and between the sleeve portions $93 and il/i to pass about the periphery and through the aperture in a refractory annulus Q disposed within sleeve Si to enter fire box l2.

With the above described arrangements the secondary air for combustion purposes absorbs heat radiated to the refractory tiles and insulation associated with the side and rear wall tubes and thus efficiently utilizes what otherwise would be waste heat in order to preheat the secondary air and thus promote efficiency of combustion within the re box.

Pulverized fuel is blown into the re box by burners projecting through openings Sii (Fig. 4) near the lower corners of the support El, platings 82, 8l, etc. constituting the rear wall of the fire box. Fuel is projected upwardly toward a point forward of the central portion of the arch toward which secondary air entering through the wall l opening till is also directed so that turbulence is created within the firebox to not only assure a proper mixture of air and fuel but also to eliminate dead spots in the re box. Secondary air is also drawn in through the side openings Tl. The gases iiow forwardly and then rearwardly in the fire box as indicated by the arrows in Fig. 2 and inasmuch as escape of gases through the rear central part of the arch is precluded by the refractory thereon they must flow through the side In escaping from the re box the gases are in contact with the refractory 34, 36 on the arch and on the side walls, respectively, and thence flow, in part directly forwardly and in part laterally over the arch refractory and thence forwardly, to the combustion chamber so that the regenerative eifect of the heated refractory assures complete combustion of the fuel.

The connection of steam and water drum itl to barrel It and of the latter to the water drums J together with the provision of circulating tubes 2i, 24, 35i, 28, iii, connected between the drums l0, 2i) and disposed in and about the fire box and combustion chamber provides for free and parallel circulation in the boiler and the scouring action of the gases on these tubes results in attaining a high generating rate. The boiler of the present invention is especially adapted for use upon the chassis of a certain modern and eicient type of locomotive and is calculated to obtain an increase of approximately thirty per cent in heat absorbed per square foot of surface and an increase of approximately fifteen per cent in the amount of fuel actually bur-ned of that fired, as compared with the conventional re tube boiler now utilized thereon. Notwithstanding this, the present boiler is also about fifteen per cent lighter than that now used. These increases in efiiciency are due in large part to the fact that in burning pulverized fuel in the enlarged fire box and combustion chamber approximately eighty per cent of the work is done therein and also because the increased gas velocity makes substantially all of the heat absorbing surfaces more effective.

It is to be understood that there are many changes and variations which may be made in the details of construction of the boiler as described herein without departing from the invention and, therefore, it is desired and intended to include all such changes within the Scope of the appended claims.

What I claim is:

l. In a locomotive type boiler; a re tube barrel disposed forwardly of the combustion chamber; a steam and water drum positioned centralh7 above the fire box and combustion chamber extending forwardly above a portion of said barrel and communicating therewith; a pair of water drums disposed adjacent the lower sides of said fire box and combustion chamber and communieating with the lower side portions of said barrel; a header disposed transversely of the boiler adjacent the lower rearward end of the combustion chamber and connected with said water drums; a header disposed transversely below and communicating centrally thereof with the steam and water drum, said header being located above said first mentioned header; and arch tubes extending rearwardly and upwardly in the fire box and connected into said headers.

2. In a locomotive type boiler; a re tube barrel disposed forwardly of the combustion chamber; a steam and water drum positioned centrally above the flre box and combustion chamber extending forwardly above a portion of said barrel and communicating therewith; a pair of water drums disposed adjacent the lower sides of said fire box and combustion chamber and communicating with the lower side portions of said barrel; a pair of headers connected with said water drums adjacent the rearward ends of the combustion chamber and re box, respectively; oirculating tubes connecting said headers and disposed above the bottom of the fire box; and circulating tubes located on the rear wall of the fire box and connecting the header at the rear portion of the latter with said steam and water drum.

3. In a locomotive type boiler; a i'lre tube barrel disposed forwardly of the combustion chamber; a steam and water drum positioned centrally above the fire box and combustion chamber and connected into the upper, rear, central portion of said barrel; a pair of water drums clisposed adjacent the lower sides of Said re box and combustion chamber and com municating with the lower side portions of said barrel; a pair of headers connected with said water drums adjacent the lower rearward ends of the combustion chamber and nre box, respectively; circulating tubes connecting said headers and disposed above the botto-m of the fire box; circulating tubes located on the rear wall of the fire box connected at their lower ends into the header at the rear portion of the fire box; and headers communicating with the steam and water drum and extending laterally therefrom and providing connections for the upper ends of the rear Wall circulating tubes.

4. In a locomotive type boiler having a fire box provided with arch tubes extending upwardly and rearwardly therethrough from the forward end to the rear wall thereof; refractory tile supported on the centrally located arch tubes from their forward ends to the rear wall of the re box and on the outer side arch tubes from the forward end of the fire box to a point short of the rear wall thereof and forming lateral openings through the arch at the sides thereof adjacent the rear portions of the side walls of the fire box; and refractory disposed on the side walls of said re box adjacent said lateral openings in the arch adapted to be contacted with regenerative effect by gases flowing from the fire box to said combustion chamber.

5. In a locomotive type boiler having a fire box provided with arch tubes extending upwardly and rearwardly therethrough from the forward end to the rear wall thereof; refractory tile supported on the centrally located arch tubes from their forward ends to the rear wall of the re box and on the outer side arch tubes from the forward end of the fire box to a point short of the rear wall thereof and forming lateral openings through the arch at the sides thereof adjacent the rear portions of the side Walls of' the fire box; circulating tubes spaced along the side walls of said re box; and refractory tile on said walls between said tubes adjacent said lateral openings in the arch adapted to be contacted with regenerative effect by gases flowing from the re box to said combustion chamber.

6, In a locomotive type boiler having a fire box provided with arch tubes extending upwardly and rearwardly therethrough from the forward end to the rear wall thereof; refractory tile supported on the centrally located arch tubes from their forward ends to the rear wall of the fire box and on the outer side arch tubes from the forward end of the re box to a point short of the rear wall thereof and forming lateral openings through the arch at the sides thereof adjacent the rear portions of the side walls of the fire box, an arch tube at each side of the fire box being depressed below the level of the adjacent inner arch tubes for at least that part of its length adjacent said openings whereby the refractory between said outer and inner tubes is inclined to form a refractory ledge contacted with regenerative effect by gases passing from the fire box to the combustion chamber.

VIRGINIUS Z. CARACRISTI. 

